Myers Briggs seems so arbitrary. Why 4 dimensions instead of 3 or 5? And is there any reliable evidence that using it actually produces better outcomes?
The Big Five model was extracted from English language words describing personality (later applied to other languages, where sometimes 6 factors are needed). It has no theory behind it (other than, "I think languages evolve to capture interpersonal dynamics").
As feanaro noted, the 4 dimensions of MBTI is fairly correlated with four of the five factors of the Big 5 (or OCEAN) model. It leaves out neuroticism, which might be helpful in a business context, since you can put a positive spin on both ends of those 4 dimensions. I've seen MBTI extended by adding a Turbulent-Assertive axis to include neuroticism without the pejorative label.
Research has shown that classifying people into the 16 types reduced the statistical predictive power. Nevertheless, the types have value for didactic purposes. It can be easier to understand personality differences by contrasting the extremes rather than the vast muddle of people near the median. Once you can see how extreme differences manifest, it is easier to recognize the more subtle (and statistically more frequent) differences.
> To further examine the universality of the Five-Factor Model, they examined how the MBTI dimensional raw scores related to the FFM/Big5 scores. They showed that FFM-Extroversion was highly correlated to MBTI-Introversion (r = -.74), FFM-Neuroticism was weakly correlated to MBTI-Introversion (r = .16), FFM-Openness was correlated to MBTI-Intuition (r = .72), and to MBTI-Perception (r = .30), FFM-Agreeableness was correlated to MBTI-Feeling (r = .44), FFM-Contentiousness correlated to MBTI-Perception (r = .49).
Those are honestly pretty high correlations for something like this. High is subjective of course. I feel like the question you want to ask is how well can you predict an MBTI score knowing only someone’s FFM.
Well if a correlation value is .7 (squared to .49) then you would expect to guess correctly about 75% of the time with just the univariate relationship (naively assuming that the underlying distribution is 50/50 to begin with, without which we would need to refer to something like a RoC AUC score…).
Big 5 is accurate but hard to explain. MBTI is fairly easy to explain and honestly it's not like astrology where it is random, an INTP does act very differently than an ENFJ
There is no material, accepted claim that you could not make another dimension, or an alternative dimension to describe personalities. Simply that these are 4 distinct and interesting ones.
A descriptive framework is of course going to be arbitrary.
